Sight for rifles



1. W. HARKOM.

SIGHT FOR RIFLES.

APPLICATION FILED FEB. 15. 1919.

Patented Nov. 9, 1920.

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UNITED STATES PTENT QFFHQE.

JOHN W. I-IARKOM, OE MELBOURNE, QUEBEC, CANADA.

. SIGHT FOR RIFLES.

Application filed February 15, 1919.

T 0 all whom it may concern:

Be it known that I, JOHN W'. HARKOM, a subject of the King of Great Britain, and resident of the village of Melbourne, in the Province of Quebec and Dominion of Canada, have invented certain new and useful Improvements in Sights for Rifles, of which the following is a full, clear, and exact description.

This invention relates to improvements in Specification of Letters Patent.

sights for rifles and the object of the invention is to provide an extremely strong method of mounting the leaf of a sight on a rifle.

A further object is to provide a strong, simple, compact and easily operated windage adjustment for the sight.

At the present time, the leaves of backsights on rifles are connected to the sight bed by a pin or screw which, owing to the small size of the parts, is necessarily a somewhat fragile affair. The result is that many sights are rendered useless by the bending or breaking of this pin. As there is usually no room for a windage adjustment to move the sight leaf as a whole, it has been customary to put such adjustment on the slide, with the result that a number of very small delicate parts must be used which are diflicult to set in poor light and which furthermore are frequently moved by accident, so that the shooting is poor.

It follows, therefore, that the logical arrangement for a windage adjuster is on the leaf and not on the slide, and also that such adjuster must be of suilicient size to be both strong and easily operated and yet not large enough to be in the way. The construction hereinafter described meets with the above requirements and in addition provides for a stronger mounting of the sight leaf than heretofore.

The device consists briefly of a sight leaf having trunnions by which it is attached to the bed both revolubly and slidably. One of the trunnions is connected to a revoluble member having a helical movement within a stationary casing. A click spring controls and indicates the position of the revoluble member and consequently of the sight leaf.

In the drawings which illustrate the invention and in which the sight used is that Patented Nov. 9, 1920.

Serial No. 277,283.

described in my former application, Ser. No. 235,801, and the rifle to which it is attached is the 191% pattern Enfield, or 1917 pattern U. S. Enfield;

Figure 1 is a plan view. 1 Figl. 2 is a cross section on the line 2-2,

Fig. 3 is a side elevation of the windage adjuster.

F a is a section on the line 42-4, Fig. 2.

F g. 5 is a section on the line 55, Fig. 2.

if 1g. 6 is a side elevation of the empty casing.

Fig. 7 is a fragmentary plan view showing the adaption of the invention to an ordinary sight leaf. Referring more particularly to the drawings, 11 designates a sight bed which may be integral avith or separate from a rifle and 12 upstanding flanges forming guards on each sideof the down-folded sight, while 13 designates a backsight such as shown in my former application. This sight is provided at its rearor lower end with a transversely disposed flat-sided portion 14:, against which the usual leaf spring 15 bears to hold the sight in either its downfolded or elevated positions. The ends of the portion 1-1 are formed into trunnions 16 and 17, by which the sight is supported. The trunnion 16 is slidably and revolubly mounted in an aperture 18 in the sight bed. The trunnion 17 is threaded and screwed into a cylindrical spindle 19, which is slidably and revolubly mounted in the adjuster body 20. Obviously the trunnion and spindle may be connected by a screw passing through either.

The body 20 is cup-shaped, as will be readily seen, and for attachment to existing rifles, is provided with a centering stud 21, which fits closely in a recess 22 in the sight bed and which is bored to form a bearing for the spindle 19. This body is provided with suitably positioned apertured lugs 23, through which screws 24 pass to secure it to the sight bed. The sides of the body may be cut away as at 25 to receive the screw heads and thus to reduce the projection of the lugs 23. In new construction, the body may be integral with the sight bed. The interior bottom surface of the body is provided with a series of regularly spaced notches or depressions 26 in circular arrangement. The spindle 19 is provided with a helical groove 27 of suitable pitch and of such length that it extends once or slightly more than once around the spindle. A pin 28 is located in the stud 21 of the body and engages in the groove 27, so that when the spindle is rotated it also moves in its axial direction and therefore moves with it the sight 13, which is connected to it by the trunnion 17. In order to rotate the spindle, a head 29 is provided having a knurled circumferential flange 30 and a plain scale receiving portion 31. This head is secured to the spindle by means of a pin 32 screwed into the head and engaging in a slot 33 in the spindle, so that the spindle is free to move in its axial direction through its head. The head is provided with a neck portion 34 of reduced diameter, which occupies the interior of the body 20 and is both revoluble and slidable therein. In order to hold the head to the body and prevent it sliding axi ally in the body, a circumferential groove 35 is formed in the neck and contains a circularly curved spring 36 having one end outwardly turned to form a catch 37 adapted to enter an aperture 38 in the body and thus hold the spring against both longitudinal movement and revolution in the body. The spring, being carried by the head and held against longitudinal movement in the body, therefore holds the head against longitudinal movement but permits its free revolution. The slot 35 may be deepened at one point 39 preferably opposite the zero point (to be later explained), so that the end 37 of the spring may be driven in and out of engagement with the body to permitseparation of the head from the body. Obviously, a pin screwed in the aperture 38 will perform the function of the spring 36 but will have the disadvantage of being a small easily lost part, whereas the spring which is not normally separable from the head will not be readily lost. The neck 34 is provided with a second circumferential groove 40, in which is seated a U-shaped spring 41 bent on the fiat to approximately semicircular form. The extremities 42 and 43 of this spring are outwardly turned, the extremity 42 being seated in a recess 44 in the outer wall of the groove 40 and the extremity 43 passing through the end of the neck, so as to engage in the depressions or notches 26 of the body and releasably hold the head at various points in its revolution. The extremities of the spring 41 being mounted in the neck, the spring moves with the neck.

The exterior of the body is provided at a suitable point with a set line, marked 0 and designated 45. The plain portion 31 of the head is provided with a scale 46 reading in opposite directions from a zero point. The graduations on this scale are the same angular distance apart as the notches 26 and each represent a suitable amount of lateral movement of the sight, for example, onehundredth of an inch or the equivalent of one minute.

While Figs. 1 and 2 illustrate this invention as applied only to the sight shown in my former application, it will be understood that it may be applied to any leaf sight. Fig. 7 shows a fragment of a sight leaf 47 of ordinary construction provided with trunnions 48. It is obvious that where adjustment for windage is desired, the trunnions may be elongated and formed as shown in Fig. 2.

The operation of the device is extremely simple. The trunnions support the sight for the usual oscillatory movement and by a very slight increase in diameter over the hinge pins ordinarily used will provide a support two or three times as strong as the hinge pin.

The spindle 19, being operatively connected to one of the sight trunnions and the other sight trunnion being free to move in the sight bed, it follows that the lateral movement of the sight is controlled by the spindle. When the head 29 is rotated the driving pin 32 therein rotates the spindle. Owing to the engagement of the pin 28 in the helical groove 27 of the spindle, the spindle acquires movement in its axial direction which moves the sight. The catch 37 holds the head against movement in the axial direction with the spindle, so that the spindle slides in or out through the head by rea son of the slot 33 in which the driving pin 32 engages. As the gradnations of the scale 46 come opposite the set line 47, the extremity 43 of the spring 41 drops into one of the notches 46 and holds the head against accidental revolution. When sufticient force is applied, the extremity of the spring climbs out of the recesses. As the spring drops into each recess a decided click is heard and also a slight shock is felt in the mechanism. Owing to the size of the parts, the spring may easily be strong enough to produce both shock and sound, which are readily noticeable, so that the device may be operated either by feel or by sound without it being necessary for the user to look at the scale. The pitch of the helical groove 27 is such that the maximum movement 011 either side of the center is attained with a half revolution of the head, so that very little manipulation is required. The groove should terminate abruptly and not taper off, so that j amming will be entirely prevented and so that it will be impossible to locate the head more than is necessary to give the maximum deflection in either direction. This will prevent straining of the pin 28 and also serve as a definite guide by which the scale may be set to zero without looking at it by merely rotating the head and counting back the EQMETRIGAL lN$TFZUMEN z 25.

requisite number of notches from the stop. The parts of the device, while large enough to be very rugged, are yet so small that they do not encumber a rifle with large projections. The construction is extremely simple and of such nature that the entrance of mud or dirt is almost entirely prevented. The device may be very easily taken apart and in addition is so constructed that it cannot be put together wrongly.

It will be remembered that the trunnion 17 was stated to be threaded and screwed into the spindle. The result is that when the spindle is rotated, the trunnion is moved longitudinally with respect to the spindle a very short distance. It is apparent that this movement is eflective on the sight either as an addition or a reduction in the amount of movement imparted by the spindle according as the two threads are pitched in the same direction or in opposite directions.

By making the groove 27 of the spindle and the trunnion thread both right hand pitch, the result is that turning the head 29 to the right gives deflection to the right to compensate for a wind coming from the right and vice versa. It therefore follows that when both of these threads are the same, the lateral movement of the sight is less than the travel of the spindle and therefore the pitch of the spindle thread should be greater by the pitch of the trunnion thread than the movement desired in the sight. If the rifle has a right hand twist, the thread on the trunnion 17 will have a right hand pitch, so as to give additional deflection to the right and reduced deflection to the left.

In the following claims, the term leaf is used generically to include all descriptions of vertically oscillating sight devices, including that shown in my former application.

Having thus described my invention, what I claim is 1. In a backsight, a sight bed, a sight leaf, trunnions on the leaf supporting it in the bed, and a windage adjuster comprising a bod secured to the sight bed and adjusting mec anism therein secured to one of the trunnions.

2. A device according to claim 1, in which the adjusting mechanism includes a head revoluble in the body and a spindle irrevoluble but slidable in the head and revolubly connected to one of the trunnions.

3. A device according to claim 1, in which the adjusting mechanism includes a spindle having a helical groove therein, a pin carried by the body engaging said groove, and means for rotating the spindle, said spindle being revolubly attached to one of the sight trunnions.

4. A device according to claim 1, in which the adjusting mechanism includes a spindle connected to one of the sight trunnions by means of a screw thread, and means for rotating and reciprocating said spindle.

5. A device according to claim 1, in which the adjusting mechanism includes a sight operating spindle, a head surrounding the spindle and arranged to impart revolution thereto, and means on the body arranged to impart reciprocatory movement to said spindle.

6. A device according to claim 1, in which the adjusting mechanism includes a head revoluble in the body, a spindle irrevoluble but movable axially through said head, means holding the head against movement in the axial direction, and means releasably holding the head at equal distances throughout its revolution.

7. In a backsight, a bed, a body fixed thereto including a hollow positioning stud passing into the bed, a helically grooved spindle journaled in said stud, a sight leaf hingedly mounted in the bed and connected to said spindle, and a pin in the stud engaging the spindle groove.

8. In a backsight, a sight bed, a sight leaf including trunnions hingedly mounted therein, a rotatable spindle, means mounted in the bed for imparting movement to the spindle in its axial direction upon revolution, and connection between the spindle and a sight leaf trunnion arranged to impart the iixipl movement of the spindle to the sight 9. A device according to claim 8, in which the connection is threaded, whereby revolution of the spindle produces movement of the sight leaf relative to the spindle opposite to that produced by the axial movement of the spindle.

10. In a backsight, a bed, a leaf hingedly mounted therein and adapted for bodily lateral movement, a screw-threaded member carried by said sight leaf, a spindle screwed upon said member and externally threaded, a body into which said spindle screws, and means for rotating the spindle to cause movement thereof in the axial direction whereby said sight leaf is moved and to simultaneously cause relative movement be tween said spindle and sight leaf in said axial direction.

11. In a backsight bed, a leaf hingedly mounted therein, and means for moving said leaf bodily in a lateral direction in the bed including a body connected to the bed, a spindle screwed into said body and connected to the leaf, and means for rotating said spindle to impart longitudinal movement thereto.

12. In a backsight, a bed, a sight leaf hingedly mounted therein, a body connected to the bed, a longitudinally slotted spindle screwed into said body and operatively connected with said leaf to move the same, and

means for rotating said spindle in the body 130 to impart longitudinal movement thereto comprising a head revoluble in the body and upon the spindle and a driving pin carried by said head engaging in the spindle slot.

13. A device according to claim 12, in which the head is cireumferentially grooved within the body and the body apertured in the plane of said head, and a curved spring mounted in the head groove and having an outturned end engaging in the body aperture whereby the head is held against movement with the spindle in a longitudinal direetion.

14. In a backsight, a bed, a leaf therein, a leaf adjusting means including a body secured to the bed, an operating head revoluble in the body and circumferentially grooved and recessed within the body, and a spring located in the head recess and connected to the head for movement therewith, said spring having one end free to engage the body, said body having a series of equidistant recesses in the path of the spring end whereby the head will be releasably locked to the body.

15. A device according to claim 14, in which the spring is U-shaped and outwardly turned at its extremities, both extremities being engaged in the head recess and one extremity projecting through the end of the head.

16. In a device of the class described, a sight leaf, an axially movable threaded spindle operatively connected to said leaf to impart lateral movement thereto, and connection between said leaf and spindle operative to move the leaf relatively to the spindle and relatively in an opposite direction to the direction of spindle movement.

17. In a device of the class described, a sight bed, a sight leaf, trunnions on the leaf supporting it in the bed and a windage adjuster for the leaf comprising a revoluble member and a differential screw connection between said member and the sight leaf in cluding one of said trunnions.

18. In a device of the character described, a sight bed, a sight leaf, trunnions on the leaf supporting it in the bed and a windage adjuster for the leaf attached to one of said trunnions, including means imposing a primary lateral movement on the leaf, and means imposing a secondary lateral movement on the leaf less than the first movement and in the opposite direction.

In witness whereof I have hereunto set in hand.

y JOHN W. HARKOM. 

